Serologic Evidence of Scrub Typhus in the Peruvian Amazon.

Using a large, passive, febrile surveillance program in Iquitos, Peru, we retrospectively tested human blood specimens for scrub typhus group orientiae by ELISA, immunofluorescence assay, and PCR. Of 1,124 participants, 60 (5.3%) were seropositive, and 1 showed evidence of recent active infection. Our serologic data indicate that scrub typhus is present in the Peruvian Amazon

Miltefosine in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania braziliensis in Brazil: A Randomized and Controlled Trial

Cutaneous leishmaniasis (CL) is characterized by skin ulcerations and occurs in rural poor areas of developing countries. It is treated with daily injections of antimony for 20 days, which is associated with irregular use and increasingly lower cure rates. Miltefosine is an oral medication with activity against the agent of CL (Leishmania). We have studied the efficacy and safety of miltefosine compared with antimony in patients with CL caused by Leishmania braziliensis in Bahia, Brazil. A total of 90 patients participated; 60 received miltefosine and 30 were treated with antimony. Six months after treatment, 75% of patients treated with miltefosine were cured, compared with 53% of the patients in the antimony group, a difference considered significant (p = 0.04). We also found that miltefosine was more effective than antimony in adults than in children. The incidence of side effects was similar with both drugs (76.7% vs. 78.3%), but all patients were able to finish the treatments. Our study shows that miltefosine is more effective than antimony for the treatment of CL in Bahia, Brazil and can contribute to the control of this disease due to its activity and easier administration

Rickettsial Disease in the Peruvian Amazon Basin.

Using a large, passive, clinic-based surveillance program in Iquitos, Peru, we characterized the prevalence of rickettsial infections among undifferentiated febrile cases and obtained evidence of pathogen transmission in potential domestic reservoir contacts and their ectoparasites. Blood specimens from humans and animals were assayed for spotted fever group rickettsiae (SFGR) and typhus group rickettsiae (TGR) by ELISA and/or PCR; ectoparasites were screened by PCR. Logistic regression was used to determine associations between patient history, demographic characteristics of participants and symptoms, clinical findings and outcome of rickettsial infection. Of the 2,054 enrolled participants, almost 2% showed evidence of seroconversion or a 4-fold rise in antibody titers specific for rickettsiae between acute and convalescent blood samples. Of 190 fleas (Ctenocephalides felis) and 60 ticks (Rhipicephalus sanguineus) tested, 185 (97.4%) and 3 (5%), respectively, were positive for Rickettsia spp. Candidatus Rickettsia asemboensis was identified in 100% and 33% of the fleas and ticks tested, respectively. Collectively, our serologic data indicates that human pathogenic SFGR are present in the Peruvian Amazon and pose a significant risk of infection to individuals exposed to wild, domestic and peri-domestic animals and their ectoparasites

Changes in the Viral Distribution Pattern after the Appearance of the Novel Influenza A H1N1 (pH1N1) Virus in Influenza-Like Illness Patients in Peru

Background: We describe the temporal variation in viral agents detected in influenza like illness (ILI) patients before and after the appearance of the ongoing pandemic influenza A (H1N1) (pH1N1) in Peru between 4-January and 13-July 2009. Methods: At the health centers, one oropharyngeal swab was obtained for viral isolation. From epidemiological week (EW) 1 to 18, at the US Naval Medical Research Center Detachment (NMRCD) in Lima, the specimens were inoculated into four cell lines for virus isolation. In addition, from EW 19 to 28, the specimens were also analyzed by real time-polymerase-chainreaction (rRT-PCR). Results: We enrolled 2,872 patients: 1,422 cases before the appearance of the pH1N1 virus, and 1,450 during the pandemic. Non-pH1N1 influenza A virus was the predominant viral strain circulating in Peru through (EW) 18, representing 57.8% of the confirmed cases; however, this predominance shifted to pH1N1 (51.5%) from EW 19–28. During this study period, most of pH1N1 cases were diagnosed in the capital city (Lima) followed by other cities including Cusco and Trujillo. In contrast, novel influenza cases were essentially absent in the tropical rain forest (jungle) cities during our study period. The city of Iquitos (Jungle) had the highest number of influenza B cases and only one pH1N1 case. Conclusions: The viral distribution in Peru changed upon the introduction of the pH1N1 virus compared to previous months. Although influenza A viruses continue to be the predominant viral pathogen, the pH1N1 virus predominated over the other influenza A viruses

Dendritic cell deficiencies persist seven months after SARS-CoV-2 infection

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin β7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19

Prevalence of Mosquito Populations in the Caribbean Region of Colombia with Important Public Health Implications

Mosquito studies are important for understanding their role in the transmission of pathogens including arboviruses, parasites, and protozoa. This study characterized the prevalence of Culicidae fauna in rural and peri-urban areas with human populations in the Colombian Caribbean region to establish the risk of transmission of mosquito-borne pathogens. From 2016 to 2017, adult mosquitos were collected in Turbaco (Bolívar), Sabanalarga (Atlántico) and Pueblo Bello (Cesar). The collections in rural areas were in the forest fragments using CDC, Shannon, and human bait traps. In peri-urban areas, Prokopack aspirator collections were used inside households. Entomological and ecological indicators were also calculated. A total of 11,566 mosquito specimens, from 13 genera and 63 species, were collected. The forests fragments of Sabanalarga and Turbaco had the highest species abundance and richness. Turbaco had the highest adult Aedes aegypti index. Arbovirus vectors were among the identified species, including Ae. aegypti, Culex quinquefasciatus, Haemagogus janthinomys, Sabethes chloropterus, Aedes angustivittatus, Mansonia titillans, Coquillettidia venezuelensis and the subgenera Culex Melanoconion. Overall, the diversity and abundance of mosquitoes present in these municipalities establish a potential disease transmission risk by these vectors